Shareholders need more power to curb director pay if companies are to rebuild public trust. That’s the conclusion of the Institute of Directors (IoD), which has been calling upon the next government to give investors a greater say over executive pay at Britain’s biggest companies.Right now shareholders have a binding vote on the company’s future pay policy every three years. However, the IoD believes it’s time to strengthen their hand. It has suggested that if 30 per cent or more investors oppose the plans, then companies should revisit their pay policy and give shareholders another vote.